Does lower dietary protein intake result in lower muscle mass in patients with end‐stage kidney failure treated by peritoneal dialysis? A retrospective study
Andrew DavenportAbstract
Background
Patients with end‐stage kidney disease (ESKD) are at risk of sarcopenia. To determine whether dietary protein intake (DPI) affects changes in body composition, changes in body composition of patients receiving peritoneal dialysis (PD) were reviewed.
Methods
A retrospective analysis of the association between DPI, estimated from the normalized protein nitrogen appearance rate (nPNA), and changes in body composition measured by bioimpedance in a cohort of established PD outpatients who had been treated with PD for >9 months, attending for routine peritoneal membrane assessments was undertaken. Patients with hospitalizations, peritonitis, and variable DPI between measurements were excluded.
Results
A total of 260 PD patients, mean age 61.6 ± 14.7 years, 58.9% male, 39.2% diabetic with a nPNA of 0.92 ± 0.25 g/kg/day were followed for a median of 13 (interquartile range, 12–15) months. Patients were divided into nPNA terciles, and whereas 56% in the highest nPNA group (nPNA >1 g/kg/day) gained lean body mass, >70% of patients in the two lower nPNA terciles lost lean body mass (P < 0.001). The annualized median change in lean body mass increased from the lowest to highest group (−3.1 to −1.0 to +0.6 kg/year; P < 0.01). On multivariable testing, the nPNA group remained independently associated with gains in lean body mass (relative risk, 2.1; P = 0.001).
Conclusion
The majority of patients with ESKD treated with PD with a nPNA of <1.0 g/kg/day lost lean body mass, whereas more than half with an nPNA of >1.0 g/kg/day had a gain. Thus, ensuring an adequate DPI is an important factor in preventing lean body mass loss in patients receiving PD.